Summary On 11 April 2000, the MilleniumYama was inbound on the St. Lawrence River. Off Godbout, Quebec, the vessel sustained a major main engine failure. Sudden stoppage of the engine caused a small fire, which was quickly put out, but the main engine could not be restarted. That evening, the vessel was towed to Baie-Comeau, Quebec, by the tug Pointe Comeau. Two days later, the vessel was towed to the port of Qubec for repair. Ce rapport est galement disponible en franais. Other Factual Information Description of the Vessel Description of the Main Engine The main engine is a Pielstick medium-speed marine engine. It drives a variable-pitch propeller and a shaft coupling generator through a reduction gearbox. The engine was designed by the Socit d'tude de machines thermiques (SEMT) and manufactured under licence in 1977 by IHICo.Ltd. in Japan. It is a single-acting, four-stroke, supercharged, trunk-piston, non-reversing, Vee-type engine. The engine develops maximum power at 520rpm. The engine has a welded main casing constructed of steel plate, forged steel, and cast steel. Welded joints are concentrated in areas of lowest stress. Weld lines subjected to high stress are carefully designed and easily accessible for inspection. The suspended crankshaft is forged in one piece. Counterweights are mounted in notches on the webs and secured at the centre by a pin. History of the Voyage On 25 March 2000, the MilleniumYama departed the port of Yali, Greece, with a cargo of 15,500tonnes of pumice, bound for Cleveland, USA. The vessel encountered relatively rough seas and high winds on the Atlantic Ocean, but the crossing was without incident. On the morning of April 11, the vessel was proceeding up the St. Lawrence, off Godbout. Before the watch changed, around 1200,2 off Pointe-des-Monts, the master reported to Marine Communications and Traffic Services (MCTS) in Les Escoumins that the vessel had passed calling-in point 2A. Meanwhile, the third engineer joined the fourth engineer in the engine room. At 1204, a thumping noise was heard by persons in the accommodation. The main engine suddenly stopped, and a total blackout followed shortly afterward. A fire in way of the No9 unit of the main engine was extinguished immediately by a response team. After surveying the damage, the chief engineer advised the master that the main engine was out of commission. The master then advised MCTS in LesEscoumins and other vessels in the area that the vessel was adrift and not-under-command. The master then informed his company of the status and position of the vessel in order to obtain towing services. The tug PointeComeau was dispatched to the site, and around 2145 it started to tow the MilleniumYama to an anchorage off Baie-Comeau. On April13 the tug Ocean Hercules towed the vessel to the port of Qubec, where it was berthed at section107 on April14, at 1655. Injuries to Persons Damage to the Vessel Inspection of the main engine revealed that the connecting rod (con-rod) had separated from piston No3.3 The piston crown had separated from the skirt, which was in pieces. The crankshaft was bent at the No4 main bearing. The exhaust valve and push rods for the exhaust and inlet valves in the No3 cylinder head were also bent. The No6 counterweight and the piston end of the No3 con-rod were jammed between the crank pin and the bottom of the liner and the casing (seeFigure1). The bottom end of the No3 con-rod punched through the right side of the main engine, damaging the casing and inspection door at unit No9. The lube oil and coolant lines and the flexible coupling were also damaged (seePhoto2). Photo 2. Bottom of the No 3 con-rod, in situ. Debris from the liner, piston, bearing shell, con-rod, counterweight, con-rod cap, pin, bearing shell, and other parts were strewn about in the crank case in way of the failed unit. To determine how and why the bottom end of the con-rod separated from the crankshaft, the two pieces of the con-rod cap, part of the upper portion of the con-rod, the four con-rod cap bolts, and the pieces of the lower bearing shell and piston skirt were sent to the TSB Engineering Laboratory for analysis. Photo 3. The four con-rod cap bolts, the two pieces of the broken cap, and part of the upper portion of the con-rod that was cut off with a torch. The letter C indicates the lower bearing shell that was broken in two. Bolts nos6-1 and 6-3 are not bent. Bolt No2-1 is deformed. Certification Vessel Certification The vessel's inspection certificates were valid. The most recent Port State Control (PSC) inspection was in Vlissingen, Netherlands, where two deficiencies, not related to engine room machinery, were noted. The vessel was built in 1979 according to requirements of the classification society, American Bureau of Shipping (ABS), and had been surveyed by this society since her construction. The owner had until 1 July 2002 to bring the vessel into compliance with the International Safety Management (ISM) Code.4 In early April2000, a short time before the occurrence, the vessel had received, from the company, a report concerning the process of implementation for ISM. Personnel Certification The chief engineer and watch officers on the MilleniumYama held the required certificates, issued by the USSR, for the power of main engine they were operating. The officers' certificates of competency were in compliance with the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW). Personnel History Chief Engineer The chief engineer held a First Class Engineer certificate (Motor), issued by the Ministry of Merchant Marine of the USSR. He started as an apprentice in 1971, and had been working as a chief engineer since 1984. He first joined this vessel on 16September1999. During his career, he gained considerable experience on this type of engine. Watch Engineer The watch engineer (8 to 12) held a Third Class Engineer certificate (Motor), issued by the Ministry of Merchant Marine of the USSR. He began his career at sea in 1981. In 1983, he completed his training as an automated systems specialist. In 1998, he was appointed to his first position as watch engineer. He first joined this vessel on 6 January 2000. Weather and Tidal Forecasts On 11 April 2000, the weather in the Baie Comeau area was partly hazy with a light wind and slight sea. Around 1204 on 11April2000, approximately four hours after forecast high tide, the vessel was in an ebb current (downbound current). The combined effect of the wind and tide produced a drift of about 1.2knots, in a direction of approximately 110 True. History of the Vessel and Main Engine Vessel Name, Ownership, and Flag Main Engine The main engine has been overhauled several times, either for preventive maintenance or as part of the five-year inspection requirements of the classification society. Since the vessel was launched in 1979, the main engine was damaged on several occasions.5 In September 1989, two cracks were discovered in the main engine casing. One crack was in way of the vibration damper, the other on the starboard side near the No12 unit inspection door. In September 1990, on a voyage from Taiwan to the United States, the main engine had a crankcase explosion. The No3 gudgeon pin was seized in the con-rod top end bushing. Number 3 crankshaft journal was also damaged. The No3 con-rod bottom end bearing shell was torn. Two more cracks were found in the casing. In November 1992, on a voyage from Taiwan to Australia, another engine crankcase explosion occurred. The No1 piston seized in its liner. The crankshaft journal in way of the No1 was out-of-round by 0.85 mm. In March 1993, on a voyage from Australia to Egypt, the main engine was damaged again. The crankshaft failed in way of the No5 bearing. Main bearing shells Nos1 to 7 and Nos1 to 12 con-rod bottom end bearing shells were damaged, as was the vibration damper. Another crack was discovered in the casing. In March 1997, on a voyage from Germany to the United States, the crankshaft journal, connecting rods and bottom end bearing shells on the no1 and 7 units of the main engine were damaged due to low oil pressure. In August 1999, the main engine failed again at sea. Repairs took several hours and involved the replacement of many parts. However, the classification society was not made aware of these repairs. As of the failure in April 2000, the subject occurrence, the main engine had accumulated about 108,000 running hours. Replacement Parts A large inventory of replacement parts, new and used, was on board. New items in inventory included bearing shells, O-rings and other small parts. Most large parts, such as cylinder heads, pistons, con-rods, and cylinder liners, were used. These used parts had been tagged Used but still good. Most of these parts had been reconditioned by engine room personnel. The parts were visually inspected, measured and, where possible, pressure tested according to the manufacturer's procedures and standards. Test results were recorded in a maintenance report. Parts that could not be repaired on board, because they required more extensive work, were sent to a repair shop. These parts were inspected by the chief engineer when they were returned to the ship. The parts repaired in a repair shop did not always have a certificate stating that they were approved and met standards. The parts inventory, which included used parts, was kept by the chief engineer. It was updated periodically. No record was kept of the quality of replacement parts. Requisitions were prepared by the chief engineer and approved by the master. When in port, used replacement parts were sometimes unexpectedly received from the company without any documentation. Connecting Rods Unit Numbering When facing forward towards the engine flywheel, cylinder units Nos1 to 6 are on the port side and cylinder units Nos7 to 12 are to starboard. Con-rods are numbered and stamped with a number from 1 to 12, indicating to which cylinder unit they belong. Numbering at Time of Occurrence Eight out of 12con-rods were marked with approval number A404B and dated 6May1977; the other four had different markings. Con-rods No2, 6, and 12 were installed in their respective cylinder units. Three replacement con-rods were in storage; only one bore the approval number A404B and was manufactured on 6May1977. However, it could not be determined whether the series of con-rods marked with approval number A404B and dated 6May1977 was original to the engine when it was manufactured in 1977, or whether it was from another source. Position of Damaged Connecting Rod On 20 August 1999, a replacement con-rod was installed in unit No3, along with new bearing shells. The con-rod was marked No11 and bore approval number A404B. Prior to that, it had been kept in the stores as a replacement. Con-Rod Maintenance Prescribed by Manufacturer The manufacturer recommends that con-rods be inspected as follows, after 24,000 running hours:6 Measure the inner diameter of the bush. Conduct a Dye Penetration Test of the con-rod cap serrated faces of the oblique bottom end joint. Any crack shall be submitted to an examination by the manufacturer, who will decide whether the con-rod cap is to be rejected. Perform a Magnetic Particle Crack-Detection Test on the con-rod bottom end screws or bolts. Failing that, carry out a Dye Penetration Test. Perform a dimensional inspection of the connecting rod bottom end bore. Figure 2. Angled split connecting rod